Stem Cells
Check out these videos to see stem cells in action Explorer: How to Build a Beating Heart NOVA: Replacing Body Parts * These cells occur naturally in our body or can be created using skin fibroblasts (special cells) to be pluripotent (able to become different cell types). Because these cells can become almost any cells in our body, they hold enormous potential in regenerative medicine. *There are in fact naturally occurring adult stem cells that can be extracted and used in culturing that the body uses naturally in its healing processes called Adult Stem Cells **Thess kinds of cells are found most in Bone Marrow but also in the brain and all throughout the body *Embryonic stem cells while they do hold moral complications, have the greatest ability to differentiate into any type of cell **should be saved for special circumstances in which only ESCs can be used to produce a certain line of stem cells **Advanced Cell Technologiy has made significant process in using the process of cloning to produce embryonic stem cells from human eggs without drestroying a fetus. ***Lab grown ESCs can help in the abundancy of ESCs without a large portion of the moral issues **Also after the desired cells are obtained from the blastocyst those cells are cultured to produce millions of ESCs that can be used to save a multitude of lives ***These cells can actually be cultured with many passages without the ESCs losing their pluripotency *iPSCs can be created by taking adult skin cells and inserting the 4 genes responsibile for pluripotency **Use patients own cells, which should theoretically reduce the immun response and rejection rate ***At the same it should be remembered that due to forced change in the make up of the cells there is a chance the body might reject these cells because of the amount of change they have undergone **These should be used as much as possible for ease of acquiring and no moral issues *Cord blood cells are extremely useful for producing blood cells and immune system cells *Tests are already being done on human patients by Geron Corp. by inserting a stem cell solution in spinal paralysis patients to produce myelin precursor cells **Already shown to be successful on rats *Also in 2008 Gary Steinberg use embryonic stem cells to renew function in the breain of rats that had lost control of that part of the brain due to strokes. *There already at least 10 lines of cells for human diseases. *Stem cells need to be differentiated or primed for differentiation **Simply implanted ESCs without differentiation cell types will with a high amount of certainty produce tumors and other complications **Several proteins have found that can egulate or halt cell division **Too many chemical changes or protein modifications will have a higher chance of rejection by the body when introduced due to the modifications that cause the cell to be too foreign for the body to accept without thinking it is foreign *Studies have shown taht there was no statistically significant difference in the overall peak endodermal differentiation efficiency of ESCs versus iPSCs. http://www.jci.org/articles/view/43853?key=1acccf69de7b78a41298 **Although this does not mean that iPSCs are a perfect substitute for ESCs **There are still consequences of the forced gene expression and suppression Bone Marrow *Bone Marrow contains naturally occuring stem cells that can easily form epideral tissues (skin) *By increasing the amount of the three major proteins responsible for bone marrow stem cell activity, the hope is that an increased amount of stem cell activity will occur in the regenerative processes. *These stem cells prove especially potent in treating patients with skin conditions or wounds Wisdom Teeth Wisdom teeth are one of the bodies naturally occuring sources for stem cells. Rather than having to go through the time and money intensive processes of reprogramming of adult stem cells, the stem cells in the cores of wisdom teeth can be used with little reprogramming. Because of how differentiated these stem cells are their pluripotentcy is limited to the facial region. At the same time this also means that the stem cells will require a smaller amount of reprogramming before they are ready to be used on patients. Organ Culturing * Hundreds of deserving people on the tranplant list die from waiting for an organ transplant each year. Of those that actually end up getting a transplant only 15% of organ transplants are successful and most only last for 10 years without failure. By using Bone Marrow stem cells or iPSCs made from patients' skin cells, working organs can be grown and produced by seeding a stripped organ scaffold or artificial scaffold made to replicate a real organ. The organs are cultured in a two step process. First the scaffold is prepared and primed for new cell growth. This can be done by either using an aritifical scaffold or by chemically stripping a donor organ of its cells leaving only the collagen and connective tissue scaffold. Second the cells are applied to the scaffold. Scientists build tissue up by seeding the scaffold with a stem cell solution of appropriate stem cells needed to create the desired organ. This process could be especially effective in the growth of a lung from a donor that died from smoking related causes. Even though the lung failed for the donor the lung could be stripped of everything especially the tar and other toxins that might have caused to lung to fail.A solution of stem cells would then be seeded on the remaining scaffold and a new lung could be grown. As long as the physical shape and structue of the organ is intact, organs that have failed can be stripped and then used to regrow a new organ on any patient. Using a scaffold for the growth of the organ is crucial in providing stem cells with the information that they need to know to differentiate into the proper functional cells. Cord-blood cells are a prime source for stem cells that are very adept at producing organs Stem cells can differentiate with little to no chemical additions or gene insertion. The cells' DNA holds all of the instruction and directions they need to differentiate into the correct cells. The cells know exactly what their roles and functions are simply by assesing their surroundings. This amazing trait of stem cells can be used to design a more refined process to differentiate stem cells into organs through the skillful use of different Bio-Materials. Cancer Stem Cell *While stem cells may not be the first thing that comes to mind when cancer is brought up, stem cells play a vital role in the way cancer actually works *At the source of almost all tumors are at least a small clump of cancer stem cells *In some cases it may not be possible to remove all of the tumor due to its location or extent of spreading **It is when these cancer stem cells are not completely dealt with that a relapse occurs and the cancer is renewed *The true source of these cells is still unknown *These cells are a valuable way to test various cancer treatments **tumors can be grown in controlled environments where the viability of different treatments can be tested **This also removes the issues and red tape involved with human testing *Some studies have shown CSCs ability to resist some types of cancer treatment *A viable approach to treating cancer is to devise solutions that effectively stop the proliferation of the CSCs into the differentiated tumor cells, effectively stoping cancer at its source *Some scientists suggest that the aggressiveness of some cancers is related to the proportion of CSCs in the tumor